Combination sis and vacuum bandage and method

ABSTRACT

A wound care bandage ( 10 ) for treating a wound ( 12 ) is provided. The bandage ( 10 ) includes an SIS layer ( 14 ) to be placed on the wound surface ( 16 ) and a cover ( 18 ) to placed over the wound ( 12 ). The bandage ( 10 ) further includes a structure ( 20 ) to provide a vacuum space ( 22 ). A method for promoting wound healing is further provided. The method includes applying the above-mentioned wound care bandage ( 10 ) to the wound ( 12 ) and creating a vacuum in the vacuum space ( 22 ) to draw blood controllably from the wound ( 12 ) into the SIS layer ( 14 ).

BACKGROUND OF THE INVENTION

[0001] The present invention relates to wound care and more particularlyto the provision of an SIS wound care cover used in combination with avacuum bandage. The invention contemplates both apparatus and a methodfor using the apparatus.

[0002] It is known to use small intestine submucosa (SIS) in wound caretreatment, particularly the application of layers of SIS directly uponan open wound that has been debrided and cleaned. SIS is described inthe following U.S. Pat. Nos.: 5,855,619, 5,866,414, 5,753,267,5,762,966, 5,755,791, 4,902,508, 4,956,178, 5,275,826, 5,281,422,4,352,463, 5,372,821, 5,445,833, 5,516,533, 5,573,784, 5,645,860,5,641,518, 5,711,969, and 5,695,998. These patents disclose the natureof SIS.

[0003] SIS has been described as a natural acellular biomaterial used torepair, support, and stabilize a wide variety of anatomical defects andtraumatic injuries. See, for example, Cook® Online New Release providedby Cook Biotech at “www.cookgroup.com”. The SIS material is a tissueengineered collagen matrix derived from porcine small intestinalsubmucosa that models the qualities of its host when implanted in humansoft tissues. Further, it is taught that the SIS material provides anatural scaffold-like matrix with a three-dimensional structure andbiochemical composition that attracts host cells and supports tissueremodeling. Surgisis™ Soft Tissue Repair Biomaterial and Oasis™ WoundDressing Biomaterial are available for remodeling partial thickness skininjuries (Cook Biotech, Bloomington, Ind.). The Oasis™ Wound Dressing isprovided in single thickness, fenestrated sheets. It will be appreciatedthat SIS is readily available for use as a wound dressing.

[0004] While small intestine submucosa is available, other sources ofsubmucosa are known to be effective for tissue remodeling. These sourcesinclude, but are not limited to, stomach, bladder, alimentary,respiratory, or genital submucosa. See, e.g., U.S. Pat. Nos. 6,171,344,6,099,567, and 5,554,389. Further, it is known that these varioussubmucosa materials may be derived from non-porcine sources, includingbovine and ovine sources. Additionally, other collagen matrices areknown, for example lamina propria and stratum compactum.

[0005] It is also known to use a vacuum treatment bandage foraccelerating wound healing. A vacuum bandage is a bandage having a coverfor sealing about the outer perimeter of the wound and under which avacuum is established to act on the wound surface. This vacuum appliedto the wound surface accelerates healing of chronic wounds. Typically,suction tubes are provided for drawing exudate away from the wound, andthe suction tubes may be used to create the vacuum under the cover. Ifthe cover is a flexible cover, which is typically more comfortable forthe patient, a porous packing may be provided under the cover to providethe space in which the vacuum is formed. Additionally, it is known aheater within a wound treatment apparatus to promote healing. Thefollowing U.S. patents establish the nature of vacuum and/or heattreatment bandages and devices: 6,095,992, 6,080,189, 6,071,304,5,645,081, 5,636,643, 5,358,494, 5,298,015, 4,969,880, 4,655,754,4,569,674, 4,382,441, and 4,112,947.

[0006] As shown, for example, in U.S. Pat. No. 5,645,081 (hereinafterthe '081 patent), a method of treating tissue damage is provided byapplying negative pressure to a wound. The negative pressure is providedin sufficient duration and magnitude to promote tissue migration inorder to facilitate the closure of the wound. FIG. 1 of the '081 patentdiscloses an open cell polyester foam section covering the wound, aflexible hollow tube inserted into the foam section at one end andattached to a vacuum pump at another end, an adhesive sheet overlyingthe foam section, and tubing to adhere to the skin surrounding the woundin order to form a seal that allows the creation of a vacuum when thesuction pump is operating. The '081 patent further teaches use ofnegative pressure between about 0.1 and 0.99 atmospheres, and that thepressure can be substantially continuous, wherein the pressure isrelieved only to change the dressing on the wound. Alternatively, the'081 patent teaches use of a cyclic application of pressure inalternating periods of application and non-application. In a preferredembodiment, pressure is applied in 5 minute periods of application andnon-application.

[0007] The following pending applications, assigned to the same assigneeas the present application is licensed, are also related to the use ofvacuum to promote healing: U.S. patent application Ser. No. 09/369,113filed Aug. 5, 1999, and titled Wound Treatment Apparatus, U.S. patentapplication Ser. No. 09/725,352 filed Nov. 29, 2000, and titled VacuumTherapy and Cleansing Dressing for Wounds, and U.S. patent applicationSer. No. 09/725,666 filed Nov. 29, 2000, and titled Wound TreatmentApparatus.

[0008] Various of prior art references teach the value of the vacuumbandage or the provision of vacuum to the surface of a chronic wound.Several Russian language articles exist that establish the efficacy ofvacuum therapy. Examples of such prior art articles, each of whichdiscusses the use of application of vacuum to a wound to promotehealing, are as follows: Vacuum therapy in the treatment of acutesuppurative diseases of soft tissues and suppurative wound, Davydov, etal. Vestn. Khir., Sept. 1988 (“the Sept. 1988 article”); Pathenogenicmechanism of the effect of vacuum therapy on the course of the woundprocess, Davydov, et al. Khirurigiia, June 1990 (“the June 1990article”); and Vacuum therapy in the treatment of suppurative lactationmastitis, Davydov, et al., Vestn. Khir., Nov. 1986 (“the Nov. 1986article”).

[0009] The Russian articles distinguish wound drainage from use ofvacuum therapy for healing, and they report that vacuum therapy resultsin faster cleansing of the wound and more rapid detoxification than withthe traditional incision-drainage method. The Nov. 1986 articledescribes the vacuum therapy protocol as 0.8-1.0 atmosphere for 20minutes at the time of surgery, and subsequent 1.5 to 3 hour treatmentsat a vacuum of 0.1 to 0.15 atmosphere, twice daily. These Russianarticles teach that use of negative pressure accelerates healing. TheRussian articles further teach using this vacuum method to decrease thenumber of microbes in the wound. The June 1990 article teaches thatvacuum therapy provides a significant antibacterial effect. The June1990 article describes the stepped up inflow of blood to the zone aroundthe wound, which leads to an increase in the number of leukocytesreaching the focus of inflamation. Moreover, the Russian articles teachimprovement of local blood circulation using vacuum therapy. TheSeptember 1988 article teaches improved inflow of blood into the woundzone, which intensifies the repair processes. The June 1990 articleteaches that vacuum therapy promotes mobilization of blood plasma,intertissue fluid, and lymph into the wound. The June 1990 articlereports that cellular and non-cellular elements of connective tissueappear twice as quickly in wounds treated with vacuum therapy.Subsequent articles and patents further develop the benefits obtainedwith vacuum therapy. The prior art, therefore, teaches the benefit andvalue of a vacuum bandage.

SUMMARY OF THE INVENTION

[0010] According to the present invention, a wound care bandage isprovided that combines the advantages of SIS and vacuum therapy tocontrol and enhance the flow of fluid from the wound bed and into theSIS material. The present invention, therefore, is a method forcontrollably drawing fluid from the surrounding tissue and into an SISlayer placed on the wound, thereby enhancing the healing andrestructuring properties of the SIS.

[0011] The present invention comprises structure to provide a spaceabove the SIS and the wound bed, in which space a vacuum is developed tocause blood flow from the wound bed into the SIS. Furthermore, themethod contemplates controlling the vacuum level and the applicationtime of the vacuum to present optimum blood flow from the wound bed intothe SIS.

[0012] In preferred embodiments, the wound care bandage includes an SISlayer to be placed in contact with the wound bed. As mentioned above,the wound care bandage further includes a structure placed over the SISlayer to provide a vacuum space between the SIS layer and a cover placedover the structure and SIS layer. The cover is coupled to the patient'sskin surrounding the wound to provide a sealed environment. A vacuumsource is coupled to the wound covering for communication with thevacuum space created by the structure. The vacuum source is used tocreate a vacuum within the sealed environment in order to draw bloodfrom the wound bed up through the SIS layer to promote the healingprocess. The vacuum suction is to be at a level sufficient to draw bloodto the SIS layer, for example, 125 mm Hg. It will be appreciated,however, that varying levels of vacuum suction and varying protocols forthe duration of application of vacuum are within the scope of thepresent invention.

[0013] In further embodiments, the space-providing structure is a porousor reticulated pad or other structure having air passageways extendingfrom the SIS layer to the cover. In still further embodiments, thespace-providing structure may be a foam ring, or it may be the coveritself, provided that the cover is sufficiently rigid.

[0014] Thus, in one aspect of this invention a wound care bandage isprovided comprising a collagen matrix formed for placement on a wound, acover configured for placement over the wound to provide a sealedenvironment around the wound and adapted for communication with a vacuumsource, and a structure for placement between the collagen matrix andthe cover and configured to provide a vacuum space. In preferredembodiments, the collagen matrix is a layer of submucosa.

[0015] In another aspect of this invention a wound care bandage isprovided comprising an SIS layer adapted to be placed on a wound, and acover configured to be placed over the wound and the SIS layer toprovide a vacuum space between the SIS layer and an inside surface ofthe cover, the space-being connectable with a vacuum source.

[0016] Still another aspect of this invention includes a method forpromoting wound healing comprising the steps of providing a wound carebandage having an SIS layer adapted to be placed on a wound, a cover tobe placed over the wound to provide a vacuum space above the wound, astructure to define the vacuum space between the SIS layer and thecover, and creating a vacuum within the vacuum space to controllablydraw blood from the wound into the SIS layer placed over the wound.

[0017] Yet another aspect of this invention is directed to a method forpromoting wound healing comprising the steps of applying an SIS layer toa wound surface, placing a support structure over the SIS layer, placinga cover over the wound, SIS layer and support structure to define avacuum space, connecting the cover to a vacuum source, and creating avacuum within the vacuum space.

[0018] An additional aspect of this invention is directed to a methodfor promoting wound healing comprising the steps of applying a collagenmatrix to a wound surface, creating a vacuum space in communication withthe wound and the collagen matrix, and generating a vacuum within thevacuum space in a magnitude and duration sufficient to draw blood fromthe wound into the collagen matrix.

[0019] A final aspect of this invention is a kit for promoting woundhealing, the kit comprising a submucosa layer for contacting the wound,a porous pad, and a cover for creating a seal around the wound andconfigured for communication with a vacuum source.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The detailed description particularly refers to the accompanyingfigures in which:

[0021]FIG. 1 is a sectional view of a debrided wound and a wound carebandage showing an SIS layer, a porous pad or filler, and a cover of thewound care bandage, and further showing the cover of the wound carebandage in communication with a tube adapted to lead to a vacuum source;

[0022]FIG. 2 is a plan view of the SIS layer shown in FIG. 1 showingfenestrations in the SIS layer;

[0023]FIG. 3 is a sectional view of another debrided wound and anotherwound care bandage including an SIS layer, a walled structure to providea vacuum space, a covering, and a vacuum tube positioned to lie underthe cover and in communication with the vacuum space at one end and avacuum source an another end;

[0024]FIG. 4 is a sectional view of another embodiment of the presentinvention showing another wound care bandage over a debrided wound andshowing the bandage including an SIS layer, a ring-shaped structuredefining a vacuum space in communication with the vacuum source, and acover positioned over the structure; and

[0025]FIG. 5 is a sectional view of another embodiment of the presentinvention showing the bandage including a semi-rigid walled structurefor defining a vacuum space in communication with the vacuum source.

DETAILED DESCRIPTION OF THE DRAWINGS

[0026] A wound care bandage 10 is provided, as shown in FIGS. 1-5, foruse with a debrided wound 12. Referring to FIG. 1, bandage 10 includes asmall intestinal submucosa (SIS) layer 14 which lies adjacent to a woundsurface 16 of wound 12. Bandage 10 further includes a cover 18 forplacement over wound 12 and a structure 20, 120, 220, or 320 positionedbetween SIS layer 14 and cover 18 in order to create a vacuum space 22.Cover 18 is coupled to a portion of the patient's skin 24 surroundingwound 12 in order to enclose wound 12, SIS layer 14, and structure 20,120, 220, or 320 within a sealed environment. Bandage 10 furtherincludes a means for communicating vacuum space 22 with a vacuum source26. The wound care bandage 10, therefore, combines the healingproperties of the SIS layer 14 with the acceleration provided by thevacuum therapy.

[0027] SIS layer 14, which is applied directly to wound surface 16, maybe fenestrated (or perforated) to prevent fluid accumulation below theSIS layer 14. Such fenestrations 28 are shown, for example, in FIG. 2.Equipment is available for fenestrating skin grafts and it iscontemplated that such equipment could also be used to fenestrate SISlayer 14. These fenestrations 28, or perforations, in the SIS layer 14permit blood from the wound 12 to migrate upwardly into the SIS layer 14and deposit cells to start the tissue growth in the SIS framework of theSIS layer 14.

[0028] Further, SIS layer 14 may be formed to include one single sheetof SIS or multiple sheets of SIS. For SIS layer 14 including multipleSIS sheets, the sheets may be positioned in any number of orientationsrelative to each other. It is further within the scope of the disclosurefor SIS layer 14 to have any reasonable thickness for its use in bandage10. It is also known in the art that larger sheets of submucosa may beformed by fusing multiple strips of submucosa tissue. See U.S. Pat. No.5,711,969. In a preferred embodiment, SIS layer 14 is sized to fit thewound and is flexible in order to allow the SIS layer 14 to conform toany complex wound or wound surface. Additionally, it is known to treatwounds with SIS provided in fresh, frozen, or lyophilized forms.Lyophilized SIS may be used in the dried form, or it may be hydratedprior to use.

[0029] In some optional embodiments, a biological glue 30 is providedbetween the debrided wound surface 16 and the SIS layer 14 in order tohold the SIS layer 14 in a stationary position against the wound surface16, as shown, for example, in FIG. 1. One type of biological glue 30used may be a fibrin sealant, for example. It is within the scope ofthis disclosure, however, to include any type of biological gluesufficient for holding the SIS layer 14 stationary relative to woundsurface 16.

[0030] SIS is intended to identify porcine small intestine submucosa.While reference is made herein to SIS, it will be appreciated that smallintestine submucosa may be obtained from other animal sources, includingcattle, sheep, and other warm-blooded mammals. Further, other sources ofsubmucosa from various tissue are known to be effective for tissueremodeling as well. These sources include, but are not limited to,stomach, bladder, alimentary, respiratory, and genital submucosa. Suchsubmucosa-derived matrices comprise highly conserved collagens,glycoproteins, proteoglycans, and glycosaminoglycans. Additionally,other collagen matrices are known that can act as a biologicalscaffolds. Thus, it is understood that while the preferred embodimentuses SIS, other collagen matrices may be used within the scope of thisinvention.

[0031] The structure of bandage 10, is provided to form vacuum space 22between SIS layer 14 and cover 18. A structure supports cover 18 whileproviding air passageways to the wound surface 16 and the SIS layer 14.As shown in FIG. 1, the structure is preferably a reticulated or porousfiller or pad 20 having airflow passageways (not shown) extendingthroughout pad 20. It is preferred that pad 20 be rather flexible toconform to any complex wound or wound surface and to be comfortable forthe patient. Further, it is preferred that the thickness of thestructure is selected to provide proper vacuum access to all parts ofthe wound to be served. It is further preferred that a thickness, t, ofthe reticulated flexible pad 20 be approximately one to two centimeters.The reticulated or porous pad 20 may be cut by the surgeon to be largerthan the SIS layer 14 and even larger than the wound 12.

[0032] Although porous pad 20 has been described above, it is within thescope of this disclosure to include any such structure which functionsto create a space between the SIS layer 14 and the cover 18 and permitsair flow from the wound 12 to transmit negative pressure to the woundsurface 16. As shown in FIG. 3, the structure 120 may be gauze, or, asshown in FIG. 4, the structure may be a foam ring 220 or other such ringto position cover 18 in spaced-apart relation to SIS layer 14. Ring 220includes an aperture defined by an inner wall 221 of the ring 220. Thevacuum space 22 is thus defined by the SIS layer 14, the cover 18, andthe inner wall 221 of ring 220.

[0033] Further, as shown in FIG. 5, for example, the structure may be arigid dome or a preferably semi-rigid dome 320 which supports the cover18 above the SIS layer 14. Semi-rigid dome 320 includes a lower member322 adapted to lie adjacent the patient's skin surrounding wound 12, anupper member 324 normally spaced-apart from SIS layer 14, and a middlemember 326 for supporting the upper member 324 in spaced-apartrelationship with the SIS layer 14. Semi-rigid dome 320 may be generallydome-shaped, for example, as well. Although such examples as porous pad20, foam ring 220, and semi-rigid dome 320 have been provided asexamples for the structure, it is within the scope of this disclosurefor bandage 10 to include any space providing structure above the SISlayer 14 and below the cover 18 for communication with a vacuum service26.

[0034] Cover 18 of the bandage 10 lies over the space-providingstructure to fully enclose the structure, SIS layer 14, and wound 12.Cover 18 is coupled to the patient's skin 24 which surrounds the wound12. For example, cover 18 may be a thin transparent, non-porous adhesivesheet to adhere to the surface of the skin 24 about the wound 12 toprovide a vacuum enclosure. An adhesive 33 for coupling cover 18 to skin24 is shown in FIGS. 1 and 3-5. A product such as Tegaderm™ (3M HealthCare Ltd., (St. Paul, Minn.)) would be suitable for the cover, forexample. It is within the scope of this disclosure, however, to includeany suitable non-porous impermeable or semi-permeable sheet. While aflexible or semi-rigid sheet is preferred for patient comfort, a rigidcover, such as a glass dome, is within the scope of this invention. Whena rigid cover is used, a separate space-providing structure is notneeded, as the rigid cover may be configured to provide the vacuumspace.

[0035] In order to encourage blood flow to the wound 12 and woundsurface 16, vacuum space 22 of wound care bandage 10 is connected withvacuum source 26. A vacuum tube 32 may be provided, for example, forfluid communication with vacuum space 22 and vacuum source 26. As shownin FIG. 1, vacuum tube 32 is coupled to cover 18 and in communicationwith vacuum space 22. A first end 40 of tube 32 includes a collar 34coupled to an aperture of the cover 18. As shown diagrammatically, asecond end 42 of tube 32 is coupled to vacuum source 26.

[0036] In other embodiments, as shown in FIGS. 3-5, for example, tube 32is placed under cover 18 and into vacuum space 22. Cover 18 is sealedaround tube 32 in order create a sealed environment for the vacuum tofunction properly. The vacuum may be provided by a suction tube disposedin the space and configured to draw excess wound drainage away from thewound. Another type of fluid connection system between a wound dressingand a vacuum source is disclosed in U.S. Pat. No. 4,969,880.Furthermore, while first end 40 of tube 32 is shown in FIGS. 3 and 4 asbeing located in the structure 120 or 220, it is understood that firstend 32 may be placed directly on the SIS layer 14. Additionally, it isunderstood that tube 32 may be a Jackson-Pratt type drain, with holesdistributed along its length adjacent first end 32.

[0037] The vacuum may be provided in vacuum space 22 for controlledperiods of time. For example, initially, the vacuum may be applied for asufficient time to draw blood into the SIS layer 14, such as up to 125mm Hg, for example. It will be appreciated that this inventioncontemplates developing different protocols for amounts of vacuum andapplication times. It will also be appreciated that the vacuum may beprovided by a perforated tube positioned and configured to carry awayexcess wound drainage.

[0038] In treating wound 12, a caretaker first cleans and prepares thewound surface 16. Once wound surface 16 is prepared, bandage 10 is to beapplied to the wound. SIS layer 14 is positioned over the wound 12 tocover the prepared wound surface 16. Structure 20, 120, 220, or 320 isplaced over the SIS layer 14 to define the vacuum space and cover 18 isplaced over the wound 12, SIS layer 14, and structure 20. Cover 18 isconnected to a vacuum source 26. Finally, suction is applied to thevacuum space 22 in sufficient magnitude and duration to draw blood fromthe wound into the SIS layer 14. Optionally, a biological glue 30 may beplaced on the wound surface 16 prior to application of the bandage 10.

[0039] Vacuum may be applied at any magnitude or duration to promoteinflow of blood from the wound into the layer of SIS. Preferably, vacuummay be applied from 0.1 to 0.99 atmospheres, and more preferably 0.1 to0.15 atmospheres. In one embodiment, vacuum is applied essentiallycontinuously until healing takes place. In another embodiment, vacuum isused in periods of application and non-application, and the structureand cover may be removed during periods of non-application. Thesealternating periods may include one or two periods of application eachday for several days. In another embodiment, the negative pressure isapplied in 5 minute periods of application and non-application.

[0040] It is known that SIS can be integrated into the wound andrestructured to resemble the surrounding tissue. Thus, while themagnitude and duration of application of vacuum may vary, in a preferredembodiment the SIS remains on the surface of the wound for the durationof treatment. In optional embodiments, additional layers of SIS may beadded as the SIS is integrated into the wound. The additional layers maybe smaller pieces to be placed on localized areas of integration, or,because the vacuum promotes blood flow into the SIS layer, may be fullsize pieces conforming to the size of the wound surface.

[0041] Thus, in one embodiment the present invention is a method fortreating wounds comprising the steps of preparing the wound surface,applying a bandage to the wound, the bandage having an SIS layer securedover the wound and a cover above the wound and the SIS layer to define avacuum space between the wound and SIS layer, and applying suction tothe vacuum space to draw blood from the wound into the SIS layer.

[0042] Although this invention has been described in detail withreference to certain embodiments, variations and modifications existwithin the scope and spirit of the invention as described and defined inthe following claims.

Claims:
 1. A wound care bandage comprising: a collagen matrix formed forplacement on a wound, a cover configured for placement over the wound toprovide a sealed environment around the wound and adapted forcommunication with a vacuum source, and a structure for placementbetween the collagen matrix and the cover and configured to provide avacuum space.
 2. The bandage of claim 1, wherein the collagen matrixcomprises a submucosa layer. 3 The bandage of claim 2, wherein thesubmucosa layer is an SIS layer.
 4. The bandage of claim 3, wherein theSIS layer includes one or more sheets of SIS.
 5. The bandage of claim 3,wherein the SIS layer is fenestrated.
 6. The bandage of claim 1, whereinthe bandage further includes a biological glue for positioning betweenthe wound and the collagen matrix for holding the collagen matrixstationary relative to the wound.
 7. The bandage of claim 6, wherein theglue is a fibrin sealant.
 8. The bandage of claim 1, wherein the coverincludes a first surface and a second surface and the first surfaceincludes an adhesive for adhering to skin adjacent the wound.
 9. Thebandage of claim 8, wherein the cover further includes a port adapted tocommunicate with the vacuum source.
 10. The bandage of claim 3, whereinthe structure is a porous pad including air passageways between thecover and the SIS layer to define the vacuum space. 11 The bandage ofclaim 10, wherein the pad is adapted to be cut to fit the wound.
 12. Thebandage of claim 10, wherein the pad comprises a flexible material. 13.The bandage of claim 10, wherein the pad has a thickness ofapproximately 1-2 centimeters.
 14. The bandage of claim 1, wherein thestructure is a ring having an aperture defined by an inner wall of thering and wherein the vacuum space is defined by the collagen matrix, thecover, and the inner wall of the ring.
 15. The bandage of claim 1,wherein the structure is a semi-rigid wall configured to liespaced-apart from the collagen matrix and adjacent to the cover.
 16. Thebandage of claim 15, wherein the semi-rigid wall includes a lower memberadapted to lie adjacent a patient's skin surrounding the wound, an uppermember configured to remain in a spaced-apart relationship from the SISlayer, and a middle member integrally coupled to the upper and lowermembers, the middle member provided to support the upper member in thespaced-apart relationship with the SIS layer.
 17. The bandage of claim15, wherein the semi-rigid wall is dome-shaped.
 18. The bandage of claim1, further comprising tubing for connecting the cover to the vacuumsource.
 19. A wound care bandage comprising: an SIS layer adapted to beplaced on a wound, and a cover configured to be placed over the woundand the SIS layer to provide a vacuum space between the SIS layer and aninside surface of the cover, the space being connectable to a vacuumsource.
 20. The bandage of claim 19, further comprising a vacuum tubefor connecting the cover to the vacuum source.
 21. A method forpromoting wound healing comprising the steps of: providing a wound carebandage having an SIS layer adapted to be placed on a wound, a cover tobe placed over the wound to provide a vacuum space above the wound, andcreating a vacuum within the vacuum space to controllably draw bloodfrom the wound into the SIS layer placed over the wound.
 22. The methodof claim 21, wherein the vacuum is applied at intervals of applicationand non-application to controllably draw fluid from the wound into theSIS layer.
 23. The method of claim 21, wherein the vacuum source isapplied at a constant rate to controllably draw blood from the woundinto the SIS layer.
 24. The method of claim 21, wherein the creatingstep includes creating a vacuum of about 0.1 to about 0.15 atmospheres.25. The method of claim 21, further comprising a structure positioned todefine the vacuum space between the SIS layer and the cover.
 26. Amethod for promoting wound healing comprising the steps of: applying anSIS layer to a wound surface, placing a support structure over the SISlayer, placing a cover over the wound, SIS layer and support structureto define a vacuum space, connecting the cover to a vacuum source, andcreating a vacuum within the vacuum space.
 27. A method for promotingwound healing comprising the steps of: applying a first collagen matrixto a wound surface, creating a vacuum space in communication with thewound and the first collagen matrix, and generating a vacuum within thevacuum space in a magnitude and duration sufficient to draw blood fromthe wound into the first collagen matrix.
 28. The method of claim 27,wherein the first collagen matrix comprises a submucosa layer.
 29. Themethod of claim 28, wherein the submucosa layer is an SIS layer.
 30. Themethod of claim 27, wherein the creating step includes positioning astructure between the first collagen matrix and the cover to provide thevacuum space.
 31. The method of claim 30, wherein the structure is aporous pad including air passageways between the cover and the firstcollagen matrix to define the vacuum space.
 32. The method of claim 30,wherein the structure is a ring having an aperture defined by an innerwall of the ring and wherein the vacuum space is defined by the firstcollagen matrix, the cover, and the inner wall of the ring.
 33. Themethod of claim 30, wherein the structure is a semi-rigid wallconfigured to lie spaced-apart from the first collagen matrix andadjacent to the cover.
 34. The method of claim 27 wherein the vacuum isprovided in periods of application and non-application.
 35. The methodof claim 27 wherein the vacuum is generated for a sufficient period oftime to begin integration of the first collagen matrix into the woundsurface, and further comprising the step of placing a second collagenmatrix over the location of the first collagen matrix.
 36. A kit forpromoting wound healing comprising: a submucosa layer for contacting thewound, a porous pad, and a cover for creating a seal around the woundand configured for communication with a vacuum source.
 37. The kit ofclaim 36, further comprising a vacuum tube.
 38. The kit of claim 37wherein the submucosa layer is SIS.